In Kraft pulp mill processes, black liquor is produced by digesters. This black liquor is subjected to an evaporation process that typically produces various classes of condensate ranging from a relatively clean condensate to a foul condensate. Foul condensates from evaporators typically contain reduced sulfur compounds and organic compounds such as methanol which contribute greatly to pulp mill water pollution in the form of biochemical oxygen demand (BOD) and toxicity and air pollution in the form of volatile organic compounds. Because of this, foul condensates are generally collected and treated by stripping the pollutants from the foul condensate. Plant steam is typically used to clean foul condensate. This approach is not always the most cost effective way for treating foul condensate,
Therefore, there has been and continues to be a need for an economical and practical approach to treating foul condensate, especially those produced in Kraft pulp mill processes.